Question about GPS and Navionics Hot Maps

[TreeMyDog]

I recently bought the Navionics HotMaps CD with 10,000+ lake maps.

You also get to choose 1 high definition map to download.

I chose the Greers Ferry Hi-def map.

My idea was to study the map at home, mark some potential waypoints, load them into my Garmin Etrex, go find them, and catch some fish.

Sounds simple enough, but the first place I go looking for is supposed to be an underwater hump that rises to within 10 feet of the surface. Totally surrounded by deep water.

I go to the waypoint, I'm ready to throw out my marker buoy, and there is no hump.

I circle the area for about 5 minutes and then give up.

Just wondering if any of you guys have had the same experience and if there is anything I am doing wrong.

My Garmin Etrex GPS is set up for the default map datum WGS84.
Signal reception was excellent. Said I was accurate to 10 feet.

Thanks.

[fished-out]

What did you use to convert the Navionics waypoints to the Garmin Etrex?

[J White]

My situation is slightly different - I have a Navionics card in my GPS,
it has my home lake in 1' contours... it shows a wonderful lookin hump,
sounds just like the one you describe, and it ain't there either

[FisherMike]

That 'hump' thief at it again.:D

[TreeMyDog]

What did you use to convert the Navionics waypoints to the Garmin Etrex?

The waypoints are already in the format of Degrees Minutes.xxx

Thats the same as I have the Garmin set for.

I also found where Navionics states that all their products use the WGS84 datum, so that's not the problem either.

[lamplighter]

i'm glad you guy's are talking about this subject. I was thinking about buying navionics hotspots 2008 to install in my eagle fishelite 480. Is it worth the money?

[Don G]

I was not aware that Garmin would accept any maps other than their own Inland Maps...They use to accept Fishing Hot Spots but have canceled their contract with them...

Please post if this is not correct..I have Garmin units and would be interested in what you find out..

[TreeMyDog]

I manually entered the coordinates into my Garmin Etrex.

My issue is with the accuracy of the maps, I think.

Any input would be helpful.

[skiptomylu]

I know from time to time on my Navionics SD maps there are thing that either are just wrong and don't even exist (showing an Island where none exist) or things like the boat lane here where I live is totally not right on the map, but for the most part I find it excellent.

Don't know about the one you have, but others have said the SD maps are the best ones. Just the other day when buying my Humminbird 1197 the guy told me the one that had the Navionics maps preloaded were not as good as the SD chips.

Me I don't know, but simply passing on what I was told.

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